Patent application title: ANTI-SHOCK ARTIFICIAL KNEE JOINT STRUCTURE

Abstract:

An anti-shock artificial knee joint includes a pivot stop block forming a
first pivot hole rotatably receiving therein a first pivot for bending
the knee joint and a second pivot hole rotatably receiving a second
pivot. A gap extending from the first pivot hole so that when the pivot
stop block is subjected to an external force induced in the process of
walking, the gap is reduced to secure the first pivot from rotation
whereby the pivot stop block rotates about the second pivot to cause the
pivot stop block to engage spring-biased pistons to thereby absorb the
external force or the impact caused by the external force. The
spring-biased pistons are provided with set screws to adjust the
cushioning effect provided by the spring-biased pistons.

Claims:

1. An anti-shock knee joint, comprising:an upper-section linking member
having an upper end forming a connection head adapted to couple to a
thigh of a limb and a lower end defining upper-section-linking-member
through holes;a pivot stop block forming a through pivot hole and a
through hole, the pivot stop block defining a gap jointing the trough
pivot hole;a cushion seat arranged between the upper-section linking
member and the pivot stop block;an intermediate-section linking member
comprising a cushion block and forming upper and lower through holes;a
lower-section pneumatic cylinder housing forming lower-section-pivot
holes and sloped bores, each sloped bore containing therein a spring and
an elastic body and further containing a piston in an upper portion
thereof and a set screw in a lower portion thereof;an upper-section pivot
extending through the through hole of the pivot stop block and the
upper-section-linking member through holes defined in the upper-section
linking member;an intermediate-section pivot extending through the upper
through holes of the intermediate-section linking member and the through
pivot hole of the pivot stop block;a lower-section pivot extending the
lower-section-pivot holes of the lower-section pneumatic cylinder housing
and the lower rough holes of the intermediate-section linking member,a
pneumatic cylinder assembly arranged inside the lower-section pneumatic
cylinder housing; anda pneumatic cylinder link rod having an upper end
coupled to the pivot stop block and a lower end coupled to the pneumatic
cylinder assembly;wherein when the pivot stop block is subjected to an
external force applied thereto, the gap is reduced to tightly secure the
intermediate-section pivot from rotation, whereby the
intermediate-section lining member is rotatable about the lower-section
pivot to have the intermediate-section linking member engaging and
supported by the pistons contained in the sloped bores of the
lower-section pneumatic cylinder housing for employing the springs,
together with the elastic bodies, to cushion a reaction force when
subjected to an external force.

Description:

BACKGROUND OF THE INVENTION

[0001](a) Technical Field of the Invention

[0002]The present invention relates to an anti-shock artificial knee joint
structure, which uses linking members and pivots to form at least two
movable jointing portions, which together with a pivot stop block and a
pneumatic cylinder assembly, allows the knee joint to operate in a safe
and smooth manner and constituting an anti-shock device that improves the
impact acting upon the body of a disabled person walking with an
artificial limb to thereby ensure a comfortable and smooth operation of
the knee joint.

[0003](b) Description of the Prior Art

[0004]With the development and progress in medical technology, disabled
persons whose legs are damaged and not allowed to walk naturally can now
be rehabilitated with the waling capability by installing an artificial
limb that incorporates with an artificial knee joint. The artificial knee
joint of the artificial limb is a mechanical device that is designed to
simulate the operation of a natural knee joint in order to provide the
most natural waking capability to the disabled persons.

[0005]Since the natural nee joint is of a very complicated structure,
although the conventional artificial knee joint employs a mechanical
structure that is effectively to substantially simulate the operation of
the natural knee joint, the conventional knee joint, in consideration of
structural strength and manufacturing costs, cannot exactly duplicate the
operation of the natural knee joint and thus is not able to provide a
user with the capability of walking in a natural way. For an adult to
take a walk with natural legs, a leg is standing upright to support the
adult's body weight, and another leg is raised and then put forward and
lowered down to set on the ground. Before it gets contact with the
ground, the knee joints of both legs are slightly bent or curved in order
to coordinate with the foot contacting the ground to alleviate the impact
acting upon the adult's body by the reaction force from the ground at the
moment that the foot contacts the ground and to set the posture for the
next step. This is the ideal way of waling. However, for a disabled
person walking with an artificial leg, when the artificial leg is raised
and put forward by the force of the thigh, the portion of the artificial
leg that corresponds to a lower leg or shank of a natural leg is not
subject to any control over the posture of the foot contacting the ground
and the angle that the knee joint bends. Thus, when the foot of the
artificial leg gets contact with the ground, most of the weight of the
disabled person falls on the heel portion of the artificial leg and an
impact caused by the reaction force is transmitted through the spine of
the disabled person to the brain and other organs of the person. When
waling in his way for a long time, the shock may cause potential damages
or discomfort to the body. Clearly enough, the conventional artificial
knee joint cannot satisfy the need of the modern users, and improvement
is thus required.

SUMMARY OF THE INVENTION

[0006]The purpose of the present invention is to provide an anti-shock
artificial knee joint, comprising an upper-section linking member forming
a connection head for coupling with a thigh and a lower-section pneumatic
cylinder housing having a lower end coupled to a shank. An
intermediate-section pivot extends through upper trough holes of an
intermediate-section linking member and a trough pivot hole of a pivot
stop block. The pivot stop block has an end coupled to
upper-section-linking-member through holes defined in the upper-section
linking member. The lower-section pneumatic cylinder housing has an upper
end coupled to lower through holes of an intermediate-section linking
member and the lower-section pneumatic cylinder housing contains therein
a pneumatic cylinder assembly having a pneumatic cylinder link rod
connected to the pivot stop block. With the coordination of the above
components with the pneumatic cylinder assembly and the pneumatic
cylinder link rod, the knee joint is allowed to bend and return to the
unbent position. Further, the lower-section pneumatic cylinder housing
forms two sloped bores in which pistons operating with springs and
elastic bodies are movably received for provide cushion effect and set
screws being provided to adjust cushioning effect, which together
constitute an anti-shock device.

[0007]When walking with the knee joint, at the time that the limb gets
contact with the ground, the weigh of a user's body falls on the knee
joint, causing the pivot stop block to tightly clamp the pivot thereby
preventing undesired bending of the knee joint and also transmitting the
weight trough the intermediate-section linking member to the anti-shock
device to alleviate the impact caused by contact with the ground,
allowing a user of the knee joint to walk in a more natural and
comfortable manner.

[0008]The foregoing object and summary provide only a brief introduction
to the present invention. To fully appreciate these and other objects of
the present invention as well as the invention itself all of which will
become apparent to those skilled in the art, the following detailed
description of the invention and the claims should be read in conjunction
with the accompanying drawings. Throughout the specification and drawings
identical reference numerals refer to identical or similar parts.

[0009]Many other advantages and features of the present invention will
become manifest to those versed in the art upon making reference to the
detailed description and the accompanying sheets of drawings in which a
preferred structural embodiment incorporating the principles of the
present invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is an exploded view showing an anti-shock artificial knee
joint constructed in accordance with the present invention;

[0011]FIG. 2 is a cross-sectional view of the anti-shock artificial knee
joint of the present invention;

[0012]FIG. 3 is a cross-sectional view of the anti-shock artificial knee
joint of the present invention in a different position;

[0013]FIG. 4 is a cross-sectional view of the anti-shock artificial knee
joint of the present invention in a finer different position;

[0014]FIG. 5 shows a sequence of drawings illustrating the operation of
the knee joint of the present invention; and

[0016]The following descriptions are of exemplary embodiments only, and
are not intended to limit the scope, applicability or configuration of
the invention in any way. Rather, the following description provides a
convenient illustration for implementing exemplary embodiments of the
invention Various changes to the described embodiments may be made in the
function and arrangement of the elements described without departing from
the scope of the invention as set forth in the appended claims.

[0017]The present invention provides an anti-shock artificial knee joint
of which the structure and operation will be now described in detail with
reference to the attached drawings for a full understanding of the
present invention. As shown in FIGS. 1-6, the anti-shock artificial knee
joint in accordance with the present invention has a structure that is
comprised of an upper-section linking member 1, an intermediate-section
linking member 2, a lower-section pneumatic cylinder housing 3, a pivot
stop block 4, a pneumatic cylinder link rod 5, and a pneumatic cylinder
assembly 6.

[0018]As shown in FIG. 1 of the attached drawings, the upper-section
linking member 1 has an upper end to which a connection head 11 is
mounted. A thigh of a user (not shown) of the artificial knee joint,
which can be for example a portion of an artificial limb or a natural
thing with suitable coupling means, is coupled to the connection head 11
by means of bolts (not shown). An upper-section pivot 10 extends trough a
through hole 42 defined in the pivot stop block 4 and also extends
upper-section-lining-member through holes 12 defined in the upper-section
linking member 1. An intermediate-section pivot 40 extends through upper
through holes 21 of the intermediate-section lining member 2 and a pivot
hole 41 formed through the pivot stop block 4. A lower-section pivot 30
extends through lower-section-pivot holes 31 defined in the lower-section
pneumatic cylinder housing 3 and lower through holes of the
intermediate-section linking member 2. The pneumatic cylinder link rod 5
has a lower end 52 coupled to the pneumatic cylinder assembly 6 received
in the lower-section pneumatic cylinder housing 3 and an upper end 51
coupled to the pivot stop block 4.

[0019]Referring to FIGS. 2-4, the upper-section lining member 1 and the
pivot stop block 4 are rotatable about the intermediate-section pivot 40
to perform a knee bending operation, which is carried out in smooth
manner with the aid of the pneumatic-cylinder link rod 5 bat is coupled
to the pivot stop block 4 and the pneumatic cylinder assembly 6. When the
knee returns back the original unbent posture, a cushion seat 13 mounted
to and between the upper-section linking member 1 and the pivot stop
block 4 and a cushion block mounted to the intermediate-section linking
member 2 eliminate the impact and/or shock caused by the returning
movement of the above components so as to ensure smooth bending and
returning operations of the anti-shock artificial knee joint of the
preset invention.

[0020]When a disabled person attempts to walk with an artificial limb,
since the artificial knee cannot operate in the same way as natural knee
joints to take a slight bending for realizing cushion effect and getting
ready for the next step, a reaction force generated at the instance when
the artificial limb gets contact with the ground causes a great impact or
shock, which makes the disabled person wearing the artificial limb
uncomfortable. To cope such a problem, in accordance with the present
invention, two sloped through holes 32 are defined in the lower-section
pneumatic cylinder housing 3 and each sloped bore 32 contains therein a
piston 321, a spring 322, an elastic body 323, and a set screw 324, which
are arranged to engage and thus support the intermediate-section linking
member 2 to thereby form, together with the pivot stop block 4, an
anti-shock device. As shown in FIGS. 5 and 6, to walk with an artificial
limb incorporating the artificial knee joint of the present invention,
one leg of the artificial limb user stands upright for bearing the
gravity of the user's body, while the other leg is raised in a slightly
bent manner. Said the other leg is moved forward and then lowered down to
step on the ground, at which moment the gravity or weight of the user's
body is moved forward to set on the anti-shock knee joint of the present
invention. Due to a gap 43 formed in the pivot stop block 4 and jointing
the pivot hole 41, when the user's body weight falls onto the pivot stop
block 4, the gap 43 is reduced, depressing and thus securing the
intermediate-section pivot 40 from rotation with respect to the pivot
hole 41. The lower through holes 22 of the intermediate-section liking
member 2 are thus rotated about the lower-section pivot 30, causing the
anti-shock device that engages and supports the intermediate-section
linking member 2 to be compressed and thus absorbing the impact or shock
and the reaction force caused by contact with the ground. In addition,
the set screw 324 provided at a lower portion of each sloped bore 32
ensures adjustment of cushioning effect of the anti-shock device to make
walking with the artificial knee joint more comfortable and smoother.

[0021]It will be understood that each of the elements described above, or
two or more together may also find a useful application in other types of
methods differing from the type described above.

[0022]While certain novel features of this invention have been shown and
described and are pointed out in the annexed claim, it is not intended to
be limited to the details above, since it will be understood that various
omissions, modifications, substitutions and changes in the forms and
details of the device illustrated and in its operation can be made by
those skilled in the art without departing in any way from the spirit of
the present invention.